1. Field of the Invention
The present invention relates to the field of medicine and health and, more specifically, to health tracking including assessing trends in health and the diagnosing and monitoring of medical conditions.
2. Description of the Related Art
In the medical profession today, the advent of high technology has provided a myriad of impressive diagnostic tools. However the focus of this medical technology has been on diagnosis of acute conditions, rather than advanced warnings and preventive advice. Routine xe2x80x9ccheckupsxe2x80x9d are the recognized method of monitoring a person""s health. Such examinations provide a physician with information relating to the patient""s condition. However, unless a patient""s checkup is fortuitously scheduled for a time at which symptoms of an ensuing illness are just developing, the checkup may not be effective in helping to detect the onset of an adverse medical condition.
Portable health monitors have been developed in the past which monitor body parameters specific to a particular medical condition. In some cases these monitors record specific parameter data, while in others they provide an output to the patient which is indicative of the physical parameters they sense. Some monitors simply provide an alarm when the parameters reach a pre-set level of particular concern. Others, specifically some portable heart rate monitors, provide a digital display of heart rate to the patient. Still others record heart rate over time. Patients use such heart rate monitors to warn them of high heart rates. Athletes use them to ensure that their physical training includes periods of elevated heart rate thought to be sufficient to promote conditioning. Similar monitors also exist for measuring other parameters, usually individually or without the capability to store the information for extended periods of time.
Absent from the prior art is a portable monitor having the capability to construct, manage, and store a detailed, multi-parametric, record of an individual""s physiological and emotional well-being that can be used for tracking and assessing general health over days, months, and years. The present invention comprises a health monitoring system including a database and data management system linked with a plurality of health trackers, each of which regularly collects various forms of data about or from a patient/subject. The preferred embodiment of the invention consists of three basic components: 1) a data management system including the database; 2) a plurality of physiological and subjective data collection devices that collect a set of timestamped serial streams from a subject; and 3) a communications system by which the data is periodically uploaded from the monitors to the database.
In the preferred embodiment the health trackers each have a portable multiparametric monitor that automatically and noninvasively monitors physiological parameters. The health trackers each preferably also include a data logger that permits and/or prompts the patient to enter subjective reports of psychological and physiological data, as well as activities and environmental conditions. Thus, a composite stream (preferably serial) of objective physiological and subjective data is created which is indicative of the overall health history of a patient/subject.
In order to be effective as a prospective diagnostic tool, the information collected is not anticipatory of any specific medical condition, but is instead broadly related to the general health of the patient. That is, the data is collected from numerous health indicators or metrics, each of which may have some relationship, or may be completely unrelated to, any particular medical condition. The composite multiparametric data streams in combination provide enough information to allow the identification of a wide variety of possible trends in the tracking data which, as an ensemble, may be indicative of any of a variety of medical conditions. Although the data collected is not specifically related to tracking any particular condition, the entire system is designed so that patterns which are characteristic of healthy subjects, as well as ill ones, can be derived from the collected data.
The preferred embodiment of the data collection portion of the invention collects a combination of sensed physiological data and subjective data entered by the patient. For subjective data collection, the patient-supplied data is solicited by the data logger using data prompts, which may be in the form of health-related questions. These questions may include interactive input formats such as body diagrams or the like. As the data is collected, it is time stamped, compressed (where appropriate) and uploaded to the database, labeled for the patient in question. The resulting health history is a combined format of objective physical parameters and subjective patient data which is time-indexed for subsequent retrieval and analysis. From these stored datastreams, trends in the data may be identified.
Each health tracker includes a means for periodically uploading the collected data to the database. In the preferred embodiment, the health trackers communicate with the database via a public information network. The monitors are connected to the network by a communications device such as a modem. Once stored in the database, the data may be later accessed by an authorized physician or by the patient. Because the data is logged by patient and time-index, the data can be recovered for a particular patient and a particular time period with relative ease. The data stored by the present invention in the database is of particular value for identifying trends in healthy persons due to the fact that it is collected regularly, irrespective of the patient""s medical condition. The invention thus provides a powerful tool previously unavailable to physicians for the early detection of adverse medical conditions.
The multiparametric physiological monitor is a portable unit for continuous monitoring of certain physical parameters of the patient. In the preferred embodiment, the monitor sensors include EKG electrodes, a chest expansion sensor, an accelerometer, a chest microphone, a barometric pressure sensor, an underarm temperature sensor, a pectoralis temperature sensor and an ambient temperature sensor. Each of the sensors provides an output signal to an analog-to-digital converter (ADC) which is controlled by a real-time (RT) controller. The RT controller is preferably a digital microcontroller which runs a program that collects data from the sensors and transmits the collected data to a second controller, referred to as the xe2x80x9cmemory serverxe2x80x9d (MS) controller, to be stored.
The MS controller, like the RT controller, is preferably a digital microcontroller. The MS controller runs a program that compresses the data received from the RT controller, where appropriate, and stores it in a random access memory (RAM). In addition, the MS controller is responsible for communications with external entities such as a database server.
In the preferred embodiment, electrocardiogram (EKG) data is reduced and compressed, and ventilation (chest expansion sensor) data is reduced. The ventilation data is reduced by storing a series of time interval/amplitude pairs that comprise a straight-line approximation of the chest expansion signal. The straight-line approximation uses the significant events in this signal, such as the inflection points in the breathing is cycle, and the start and stop of breathing plateau periods (i.e. extended times of stable chest circumference), as well as sharper inflections associated with sneezing, coughing or retching.
EKG data, sampled most frequently, is reduced by storing only timing information for each heartbeat (QRS complex) and, once per minute, storing the median values of various components of a straight-line approximation of the QRS complex. The heartbeat interval information is compressed by storing the differences in interval duration rather than the interval itself where possible, and storing the interval differences in formats which take advantage of their compressed size.
The RAM is divided into three regions: 1) the scratchpad; 2) the warehouse (long-term storage of all but 8-bit EKG data); and 3) the 8-bit EKG data area. As data is received, it is placed in the scratchpad. As time permits, data is read from the scratchpad, processed, and stored in the warehouse or the EKG zone, depending on the data type and size. The MS controller stores data received from the RT controller in the scratchpad in the packetized format in which it was received. When not busy with other tasks, the MS controller processes data temporarily stored in the scratchpad and places it in variable-length fields in the warehouse or fixed-length fields in the EKG zone. The data in the warehouse is tagged using a coding method which identifies the data type with a particular sequence of leading bits. This allows proper reassembling of data as it is read out of memory.
In the preferred embodiment, the subjective data logger runs a user-friendly data collection program which prompts the patient to report subjective data or simply serves to structure a voluntary submission of a report. This data is timestamped and stored in a local memory unit of the data logger for later uploading to the database. The monitor and the data logger may be linked together to connect to the database as a single unit via a public data network or other communication medium. Alternatively, either of the monitor and the data logger may individually connect to the database.
One particular feature of the present invention involves the use of a capsule which contains a patient""s medication, along with a miniature pulse generator and transmitter. When the capsule is ingested and dissolves in the patient""s stomach acid, the medication is liberated and the transmitter is activated. The transmitter transmits a pulsed signal which is uniquely identified with the medication in the capsule. The signal is detected by the EKG electrodes of the monitor on the surface of the patient""s skin, and is decoded by the monitor firmware to automatically identify which drugs are ingested by the patient and when they are taken.